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		<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
        <title></title>
		<style>
			
		</style>
		<script>
			/*let t = (function (){
				function add(a,b){
					console.log(a+b);			
				}
				function isFunction(a,b){
					console.log(a+b);			
				}
				function add1(a,b){
					console.log(a+b);			
				}
				function isFunction2(a,b){
					console.log(a+b);			
				}	

				return {
					add:add,
					isFunction:isFunction
				}
			})();

			let {add,isFunction} = t;

			add(1,2);
			isFunction(1);

			Math.abs();
			Math.floor();*/

			let {abs,max} = Math;

			console.log(abs(-1));
			console.log(max(1,2,3));

			let o = {a:1,b:2};

			let {a:usersNum=1000,b,c=10} = o;

			console.log(usersNum);
			console.log(c);


		</script>
	</head>

	<body>
		
	</body>
</html>